xref: /netbsd-src/crypto/external/bsd/openssl.old/dist/doc/man3/ASN1_STRING_length.pod (revision 4724848cf0da353df257f730694b7882798e5daf)
1*4724848cSchristos=pod
2*4724848cSchristos
3*4724848cSchristos=head1 NAME
4*4724848cSchristos
5*4724848cSchristosASN1_STRING_dup, ASN1_STRING_cmp, ASN1_STRING_set, ASN1_STRING_length,
6*4724848cSchristosASN1_STRING_type, ASN1_STRING_get0_data, ASN1_STRING_data,
7*4724848cSchristosASN1_STRING_to_UTF8 - ASN1_STRING utility functions
8*4724848cSchristos
9*4724848cSchristos=head1 SYNOPSIS
10*4724848cSchristos
11*4724848cSchristos #include <openssl/asn1.h>
12*4724848cSchristos
13*4724848cSchristos int ASN1_STRING_length(ASN1_STRING *x);
14*4724848cSchristos const unsigned char * ASN1_STRING_get0_data(const ASN1_STRING *x);
15*4724848cSchristos unsigned char * ASN1_STRING_data(ASN1_STRING *x);
16*4724848cSchristos
17*4724848cSchristos ASN1_STRING * ASN1_STRING_dup(ASN1_STRING *a);
18*4724848cSchristos
19*4724848cSchristos int ASN1_STRING_cmp(ASN1_STRING *a, ASN1_STRING *b);
20*4724848cSchristos
21*4724848cSchristos int ASN1_STRING_set(ASN1_STRING *str, const void *data, int len);
22*4724848cSchristos
23*4724848cSchristos int ASN1_STRING_type(const ASN1_STRING *x);
24*4724848cSchristos
25*4724848cSchristos int ASN1_STRING_to_UTF8(unsigned char **out, const ASN1_STRING *in);
26*4724848cSchristos
27*4724848cSchristos=head1 DESCRIPTION
28*4724848cSchristos
29*4724848cSchristosThese functions allow an B<ASN1_STRING> structure to be manipulated.
30*4724848cSchristos
31*4724848cSchristosASN1_STRING_length() returns the length of the content of B<x>.
32*4724848cSchristos
33*4724848cSchristosASN1_STRING_get0_data() returns an internal pointer to the data of B<x>.
34*4724848cSchristosSince this is an internal pointer it should B<not> be freed or
35*4724848cSchristosmodified in any way.
36*4724848cSchristos
37*4724848cSchristosASN1_STRING_data() is similar to ASN1_STRING_get0_data() except the
38*4724848cSchristosreturned value is not constant. This function is deprecated:
39*4724848cSchristosapplications should use ASN1_STRING_get0_data() instead.
40*4724848cSchristos
41*4724848cSchristosASN1_STRING_dup() returns a copy of the structure B<a>.
42*4724848cSchristos
43*4724848cSchristosASN1_STRING_cmp() compares B<a> and B<b> returning 0 if the two
44*4724848cSchristosare identical. The string types and content are compared.
45*4724848cSchristos
46*4724848cSchristosASN1_STRING_set() sets the data of string B<str> to the buffer
47*4724848cSchristosB<data> or length B<len>. The supplied data is copied. If B<len>
48*4724848cSchristosis -1 then the length is determined by strlen(data).
49*4724848cSchristos
50*4724848cSchristosASN1_STRING_type() returns the type of B<x>, using standard constants
51*4724848cSchristossuch as B<V_ASN1_OCTET_STRING>.
52*4724848cSchristos
53*4724848cSchristosASN1_STRING_to_UTF8() converts the string B<in> to UTF8 format, the
54*4724848cSchristosconverted data is allocated in a buffer in B<*out>. The length of
55*4724848cSchristosB<out> is returned or a negative error code. The buffer B<*out>
56*4724848cSchristosshould be freed using OPENSSL_free().
57*4724848cSchristos
58*4724848cSchristos=head1 NOTES
59*4724848cSchristos
60*4724848cSchristosAlmost all ASN1 types in OpenSSL are represented as an B<ASN1_STRING>
61*4724848cSchristosstructure. Other types such as B<ASN1_OCTET_STRING> are simply typedef'ed
62*4724848cSchristosto B<ASN1_STRING> and the functions call the B<ASN1_STRING> equivalents.
63*4724848cSchristosB<ASN1_STRING> is also used for some B<CHOICE> types which consist
64*4724848cSchristosentirely of primitive string types such as B<DirectoryString> and
65*4724848cSchristosB<Time>.
66*4724848cSchristos
67*4724848cSchristosThese functions should B<not> be used to examine or modify B<ASN1_INTEGER>
68*4724848cSchristosor B<ASN1_ENUMERATED> types: the relevant B<INTEGER> or B<ENUMERATED>
69*4724848cSchristosutility functions should be used instead.
70*4724848cSchristos
71*4724848cSchristosIn general it cannot be assumed that the data returned by ASN1_STRING_data()
72*4724848cSchristosis null terminated or does not contain embedded nulls. The actual format
73*4724848cSchristosof the data will depend on the actual string type itself: for example
74*4724848cSchristosfor an IA5String the data will be ASCII, for a BMPString two bytes per
75*4724848cSchristoscharacter in big endian format, and for a UTF8String it will be in UTF8 format.
76*4724848cSchristos
77*4724848cSchristosSimilar care should be take to ensure the data is in the correct format
78*4724848cSchristoswhen calling ASN1_STRING_set().
79*4724848cSchristos
80*4724848cSchristos=head1 RETURN VALUES
81*4724848cSchristos
82*4724848cSchristosASN1_STRING_length() returns the length of the content of B<x>.
83*4724848cSchristos
84*4724848cSchristosASN1_STRING_get0_data() and ASN1_STRING_data() return an internal pointer to
85*4724848cSchristosthe data of B<x>.
86*4724848cSchristos
87*4724848cSchristosASN1_STRING_dup() returns a valid B<ASN1_STRING> structure or B<NULL> if an
88*4724848cSchristoserror occurred.
89*4724848cSchristos
90*4724848cSchristosASN1_STRING_cmp() returns an integer greater than, equal to, or less than 0,
91*4724848cSchristosaccording to whether B<a> is greater than, equal to, or less than B<b>.
92*4724848cSchristos
93*4724848cSchristosASN1_STRING_set() returns 1 on success or 0 on error.
94*4724848cSchristos
95*4724848cSchristosASN1_STRING_type() returns the type of B<x>.
96*4724848cSchristos
97*4724848cSchristosASN1_STRING_to_UTF8() returns the number of bytes in output string B<out> or a
98*4724848cSchristosnegative value if an error occurred.
99*4724848cSchristos
100*4724848cSchristos=head1 SEE ALSO
101*4724848cSchristos
102*4724848cSchristosL<ERR_get_error(3)>
103*4724848cSchristos
104*4724848cSchristos=head1 COPYRIGHT
105*4724848cSchristos
106*4724848cSchristosCopyright 2002-2020 The OpenSSL Project Authors. All Rights Reserved.
107*4724848cSchristos
108*4724848cSchristosLicensed under the OpenSSL license (the "License").  You may not use
109*4724848cSchristosthis file except in compliance with the License.  You can obtain a copy
110*4724848cSchristosin the file LICENSE in the source distribution or at
111*4724848cSchristosL<https://www.openssl.org/source/license.html>.
112*4724848cSchristos
113*4724848cSchristos=cut
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